1. Technical Field
The present invention relates to a projector, a display image adjusting method, a program for executing the display image adjusting method, and a recording medium having recorded thereon the program.
2. Related Art
Projectors modulate a light flux emitted from a light source according to an input image signal and project the modulated light flux on a screen on magnified scale. Among the projectors, a so-called front projector that has a screen and a projector to be separately provided is widely used for presentation for business use or a personal home theater.
In such a projector, if a projection lens of the projector is arranged to face the screen, no problem occurs in a projection image. However, if the surface of the screen is inclined with respect to the projector, the projection is inclined, and a keystone distortion occurs in the projection image accordingly.
For this reason, there is known a projector that has a function of correcting the keystone distortion without changing the positional relationship between the projector and the screen.
Further, when the projector and the screen are provided, a distance between the projector and the screen changes according to situations. Accordingly, it is necessary to perform zoom or focus adjustment while viewing an image projected on the screen.
In the related art, generally, an observer of the projector operates the projector so as to perform such a keystone distortion correction or focus adjustment. In order to automize the above-described functions, there is suggested a projector that has an image-capturing device, such as a CCD (Charge-Coupled Device) camera thereon and automatically performs the keystone distortion correction and the zoom and focus adjustment on the basis of an image captured by the image-capturing device (for example, see JP-A-2000-241874 and JP-A-2005-318510).
However, in the above-described projector that can automatically perform the keystone distortion correction and the zoom and focus adjustment, the image-capturing device operates only when the projector is initially installed. Meanwhile, after an image is protected, the image-capturing device does not operate. In particular, in the case of a fixed projector, if the projector is set once, the projector seldom moves. Accordingly, since the mounted image-capturing device does not operate after the installment, the image-capturing device becomes useless.
Meanwhile, in an image display device including such a projector, it is necessary to reduce power consumption in a view of energy conservation.